PORT ELIZABETH, South Africa, Feb 22 (Reuters) - South Africa were 192 for four in their second innings with a lead of 369 over Australia at the close of play on the third day of the second test at St George's Park on Saturday. Scores: South Africa 423 (JP Duminy 123, AB de Villiers 116, D. Elgar 83, F. Du Plessis 55; N. Lyon 5-130) & 192-4 (H Amla 93 not out) v Australia 246 (D. Warner 70; M. Morkel 3-63, V. Philander 3-68) (Compiled by Nick Said; editing by Ed Osmond; nick.said@thomsonreuters.com +27832722948 Messaging nick.said.thomsonreuters.com@reuters.net; To sign up for our Global Sports Forum chatroom, click on https://forms.thomsonreuters.com/global_sports_forum)